Compact injection device with telescoping components

ABSTRACT

An injection device uses telescoping and/or nested components and other features to make the overall device compact in size. The device is configured to have a storage position and an extended position, such that its needle is positioned within the housing of the device in a storage position, with the needle extending beyond the device housing when needed for an injection. The telescoping plunger mechanism has a storage position and an extended position for use. The device includes a needle depth cover, which extends from the device housing for use, and guides the user as to the correct depth for the needle to penetrate the user&#39;s skin. A switch allows different depth settings, for example allowing a deeper penetration for injection into a leg, and shallower penetration for injection into an arm.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No.62/358,645, filed Jul. 6, 2016

FEDERALLY-SPONSORED RESEARCH

None

BACKGROUND

The present application relates to the field of injection devices suchas syringes, as used for injections of medications.

BRIEF SUMMARY

The injection device described herein uses telescoping and/or nestedcomponents and other features in order to make the overall devicecompact in size. The compact design allows the device to be easilycarried or worn by a person, such as in the form of a bracelet orpendant. The device is configured to have a storage position and anextended position, such that its needle is positioned within the housingof the device in a storage position, with the needle extending beyondthe device housing when needed for an injection. The telescoping plungermechanism also has a storage position and an extended position for use.The device includes a needle depth cover, which extends from the devicehousing for use, and guides the user as to the correct depth for theneedle to penetrate the user's skin. A switch allows different depthsettings, for example allowing a deeper penetration for injection into aleg, and shallower penetration for injection into an arm.

In an embodiment of the injection device, there is: a main casecontaining a syringe body; a two-piece telescoping plunger movablyengaged within the syringe body, the telescoping plunger including aplunger body and a plunger extension; a tubular needle movably engagedwith the syringe body; a medicine volume chamber within the syringebody. The device may expand from a storage position to a deploymentposition, thereby expanding the telescoping plunger and being capable ofdelivering the medicine volume chamber's contents through the tubularneedle to a body by depressing the telescoping plunger.

In an embodiment of the injection device, there is an injection device,comprising: a syringe body; a two-piece telescoping plunger movablyengaged within the syringe body, the telescoping plunger including aplunger body and a plunger extension; a tubular needle movably engagedwith the syringe body; a medicine volume chamber within the syringebody; whereby said device may expand from a storage position to adeployment position, thereby expanding the telescoping plunger and beingcapable of delivering the medicine volume chamber's contents through thetubular needle to a body by depressing the telescoping plunger.

An embodiment of the device may further include a retractable needledepth cover movably engaged with the main case and that surrounds thetubular needle when the tubular needle is in a storage position.

An embodiment of the device may further include a retractable needledepth cover that retracts to a pre-set depth as the tubular needleenters into the body, thereby limiting the needle's penetrative depthinto the body, and in which the pre-set depth is controlled by a switch.

An embodiment of the device may further include a pull plug removablyengaged with the needle's sharp end, with the pull plug also removablyengaged with the main case when the injection device is in the storageposition. Removing the pull plug may extend the needle into a deployedposition and thereby engage at least one set of needle barbs with atleast one set of plug barbs.

An embodiment of the device may further include a switch to control themovement of the device from the storage position to the deployedposition.

An embodiment of the device may further include a spring to expand theplunger body relative to the plunger extension.

An embodiment of the device may further include the plunger body and theplunger extension engaged with one another by at least one longitudinalfinger and at least one recess when the plunger is in its expandedposition.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows an exploded view of an embodiment of the present device

FIG. 2 shows a right side elevation view of an embodiment of the presentdevice

FIG. 3 shows a front elevation view of an embodiment of the presentdevice

FIG. 4 shows a left side elevation view of an embodiment of the presentdevice

FIG. 5 shows a cross-sectional view of an embodiment of the presentdevice

FIG. 6 shows a cross-sectional view of an embodiment of the presentdevice

FIG. 7 shows a perspective view of an embodiment of the present devicein its storage position

FIG. 8 shows a perspective view of an embodiment of the present devicein its deployed position

FIG. 9 shows a perspective view of an embodiment of the present devicein its deployed position

FIG. 10 shows a perspective view of an embodiment of the present devicein its deployed position with its needle depth cover compressed, asduring an injection

FIG. 11 shows a perspective view of an embodiment of the present devicein its deployed position with its needle depth cover compressed, asduring an injection

FIG. 12 shows a perspective view of an embodiment of the present devicein its deployed position FIG. 13 shows a cross-sectional view of anembodiment of the present device in its deployed position

FIG. 14 shows an enlarged view of the needle in its deployed position

FIG. 15 shows a cross-sectional view of the syringe plunger in itsstorage position

FIG. 16 shows a cross-sectional view of the syringe plunger in itsextended position

DETAILED DESCRIPTION

In the preferred embodiment, the medicine contained in the device isepinephrine, as used for emergency treatment of anaphylaxis and/oranaphylactic shock. Those who are afflicted with severe,life-threatening allergies are advised to carry a kit with them at alltimes that contains a supply of epinephrine and means for injecting saidmedicine. However, such kits typically are bulky in size, primarily dueto the elongated shape of a syringe. The present injection deviceincludes numerous features that allow it to have a compact storage size,while expanding into a deployment position for injection use. Of course,the present injection device is not limited to delivering epinephrine,but can be used for any suitable injectable medicine.

In one embodiment of the device, and in reference to FIG. 1, there is amain case 7. Main case 7 is approximately tubular in shape, with mostother components housed within it. Moving inward, needle depth cover 3is slideably arranged within main case 7, as will be further detailed.For spatial reference throughout this specification, “upper” refers tothe plunger end of the overall device, and “lower” refers to theopposing needle end of the device, with “upward” and “downward”similarly referenced.

A needle depth cover return spring 22 is positioned to extend needledepth cover 3 for use, with the lower end of the spring configured toabut the end of depth cover 3. The upper end of spring 22 abuts a flange1A on a syringe barrel body 1, with a portion of spring 22 surroundingthe lower portion of syringe barrel body 1. This spring positioning canbe seen in section B-B, FIG. 5, and section A-A, FIG. 6. Tabs 3 b ondepth cover 3 engage with main case 7, providing a limit to the travelof the cover 3 relative to case 7.

Telescopic syringe plunger body 2, telescopic syringe plunger extension9, and syringe plunger top 17, together form the full plunger assembly.Retainer 11 engages with barrel body 1 to contain plunger body 2. InFIG. 2-7, the device is shown in its storage position, where syringeplunger extension 9 is positioned inside of syringe plunger body 2, in atelescopic, or nested configuration. That is, the plunger is comprisedof concentric tubular sections designed to slide into one another. Indeploying the overall device to its extended position for use ininjection, syringe plunger extension 9 slides relative to syringeplunger body 2, forming an extended, depressable plunger, as will befurther explained.

With reference to FIGS. 15 and 16, the plunger assembly includes theconcentric tubular sections of extension 9 and plunger body 2. Theprimary purpose of such an assembly is to create a plunger which in astorage position is more compact (that is, shorter in overall length)than the length required by the plunger for use in delivering medicinethrough a needle, as when the device is in an extended position anddeployed for use. When switch 12 (as seen in FIG. 1) is moved and allowsthe device to extend, plunger extension 9 is released with plungerspring 25 causing extension 9 to move upward relative to plunger body 2.Herein, switch 12 includes an element which interlocks with a barb-typeelement on extension 9, thereby releasing extension 9 under the force ofspring 25. Longitudinal fingers 9 a, which remain compressed in thestorage position, are released outward when spring 25 pushes plungerextension 9 into its final position. Fingers 9 a engage in recesses 2 ain plunger body 2, thus locking extension 9 in an extended positionrelative to plunger body 2. Thus, a full length plunger has beenconfigured.

Again in reference to FIG. 1, there is a needle 8, which is a hypodermictype for injection of medicine into a body. As seen in the crosssectional views of FIG. 5 and FIG. 6, which depict the device in itsstorage position, needle 8 passes through the medicine volume chamber 5.Thus, a mid-portion of the length of needle 8 is positioned withinchamber 5, with an upper portion of needle 8 above chamber 5, and alower portion of needle 8 positioned below chamber 5. As needle 8 is atubular hypodermic type, this results in the inner passage of needle 8containing medicine when the device is in its storage position.

In the storage position, the upper portion of needle 8 rests in theinner bore 24 of telescopic syringe plunger body 2, and above chamber 5.Needle 8 is in a retracted, nested position inside telescopic syringeplunger body 2, with the medicine volume contained in the undeployedstorage position. The clearance between needle and plunger body 2 issuch that a small amount of medicine from chamber 5 may be presentinside the bore 24 of body 2 and on the outside of needle 8. Needle 8contains at least one needle bore opening 32, as shown in FIG. 14, whichallow medicine to enter the inner bore of needle 8.

Needle barbs 30 are included on the outer diameter of the upper end ofneedle 8. When the device deploys from its storage position to itsextended position, needle 8 slides downward, with the needle's upper endtraveling downward, and needle barbs 30 mate with catch plug barbs 15 a,where catch plug barbs 15 a are contained in the inner bore of catchplug 15. Catch plug 15 is positioned directly below chamber 5. Thus, asthe device is deployed, needle 8 moves downward with the upper end ofneedle 8 exiting the inside bore of extension 9, until needle barbs 30(on the OD of the upper end of needle 8) engage with plug barbs 15 a,and needle 8 is therefore positioned entirely below chamber 5. FIG. 14shows an enlarged view of the interlocking barbs of the needle 8 andbushing 13. Bushing 13 is positioned directly below catch plug 15, andtogether with guide seal 14 align and secure needle 8 within syringebody 1.

As the device is deployed, depth cover spring 22, which is incompression when the device is in its storage position, extends depthcover 3 downward, as seen in the deployed view of the device in FIG. 9.Pull plug 18 includes a plug stop 18 a, which is removably affixed incover hole 3 a of needle depth cover 3. Plug 18 may be made from avariety of pliable materials, such as various rubber and plasticcompounds. Plug stop 18 a is removably affixed to the sharp end portionof needle 8, such that when the device deploys and depth cover 3 extendsdownward, needle 8 travels downward within the overall device, inparticular relative to the inside bore of extension 9. Thus, thefrictional fit between plug stop 18 a and needle 8 is what creates thedownward travel of the needle during deployment, providing the requiredforce to engage the interlocking barbs at the top end of the needle.

Creating needle travel as part of device deployment is one of severalpurposes of needle depth cover 3. A second purpose is that of a depthgauge, such that a user knows how deeply the needle should be insertedinto a body. When the device is deployed and ready for injection, thelower end of needle 8 is approximately flush with the front surface ofneedle depth cover 3. As the needle is inserted into a body, the bodypresses against the front surface of needle depth cover 3, pushing depthcover 3 upward and compressing spring 22. The needle is inserted to thedepth at which need depth cover 3 can no longer be compressed, asdetermined by the arm/leg depth settings, which will be furtherexplained.

An additional purpose of the needle depth cover 3 is creating a guardaround needle 8. When an injection is complete, and the needle isremoved from a body, spring 22 causes needle depth cover 3 to againextend downward, covering needle 8, thus providing shielding andprotection of the sharp needle end.

Plug loops 18 b also serve as part of the deployment mechanism. As seenin FIG. 7 and FIG. 8, loops 18 b wrap around the device in a low-profilemanner when the device is in its storage position. For deployment, loops18 b peel off the device so that that a user's fingers can grasp theloops. As previously described, plug stop 18 a serves in part to pullneedle 8 downward within the device as the device moves to its extendedposition. A user then pulls pull plug 18 off of needle 8; this removalaction creates additional tensile force on the needle, which may furtherseat needle barbs 30 into plug barbs 15 a. Pull plug 15 also, of course,shields the lower end of needle 8 during storage.

As seen in FIG. 1, switch 12 serves to unlock the device and release itfrom its storage position to its extended position. Switch 12 is amechanical type, and includes tab 12 a and flange 12 b. Window 23 allowsthe user to see an indication of the device's position. As the switch ismoved from lock position to “arm” or “leg” position, with visualindicators included for such purpose, tab 12 a and flange 12 b rotatesuch that they disengage from their mating surface of tab 3 a on depthcover 3. The “leg” position of switch 12 allows the needle depth cover 3to retract further during the insertion of a needle into a body,compared to the arm setting. Thus, the user is guided to a deeper needlepenetration for leg use. Of course, the arm and leg depth settings arejust examples of depth guides. For instance, depth guides could also becorrelated according to use of not just of an injection location, but ofthe age/size of a user, such as child or adult.

The overall injection device may be configured to be worn by a person,in forms such as but not limited to a wristband, pendant, etc. Thelength of a traditional syringe makes it impractical to be a worndevice, but the compact form of the present device allows practicalwearability. FIG. 1 and FIG. 7 show sleeve 20, which houses the overallinjection device, and includes slots 20 a, into which a wristband orother band can mount. Thus the overall device can be worn as wristband,pendant, etc., and therefore easily carried by those who requireimmediate access to medicine at all times. The device may include casecap 21 as shown in FIG. 1. Cap 21 is removably attached to syringeplunger top 17, with the enclosed space between creating space formedicine in pill form 10, where the pills may be antihistamines or anyother desired drug. This integration allows for the inclusion of aplurality of drug delivery types/forms in a single device.

The following summarizes the overall device in use. The device isremoved from sleeve 20. Switch 12 is moved from the position locking theoverall device, to a position that causes the device to deploy (such asan “arm” or “leg” setting), with switch mechanisms allowing springs 25and 22 to expand the device. Needle 8 travels downward, with the useralso pulling on pull plug 18, causing needle barbs 30 to mate with catchplug barbs 15 a. Syringe plunger extension 9 travels upward, withlongitudinal fingers 9 a fitting into recesses 2 a, thereby forming afull-length plunger. Needle depth cover 3 moves downward under the forceof spring 22. Pull plug 18, which engages the sharp end of needle 8, isremoved by the user from depth cover 3 and needle 8, revealing the sharpend of needle 8. The device is now ready for injection. The user placesthe front of needle depth cover 8 against a body and presses downward,until the needle depth cover can depress no further, marking that theneedle has entered the body to the correct depth. Plunger 2 is thendepressed, forcing medicine through needle 8 and into the body. When theinjection is complete, the device is removed from the body, causingdepth cover 3 to return to its fully extended position, and therebyshielding the sharp end of needle 8.

Although the present system has been described with respect to one ormore embodiments, it will be understood that other embodiments of thepresent system may be made without departing from the spirit and scopeof the present system. Hence, the present system is deemed limited onlyby claims and the reasonable interpretation thereof.

What is claimed:
 1. An injection device, comprising: a syringe body; atwo-piece telescoping plunger movably engaged within the syringe body,the telescoping plunger including a plunger body and a plungerextension; a tubular needle movably engaged with the syringe body,wherein the tubular needle is located in the telescoping plunger whenthe device is in a storage position; a medicine volume chamber withinthe syringe body; whereby said device is configured to expand from thestorage position to a deployment position, to expand the telescopingplunger, and to deliver a medication in the medicine volume chamberthrough the tubular needle to a body by depressing the telescopingplunger; and wherein a portion of the tubular needle is positionedwithin the medicine volume chamber when the injection device is in thestorage position.
 2. The device of claim 1, further comprising aretractable needle depth cover movably engaged with the syringe body andsurrounding the tubular needle when the tubular needle is in the storageposition.
 3. The device of claim 2, in which the retractable needledepth cover is configured to retract to a pre-set depth as the tubularneedle enters into the body, thereby limiting the needle's penetrativedepth into the body.
 4. The device of claim 3, in which the pre-setdepth is controlled by a switch.
 5. The device of claim 2, in which thedepth cover is configured to return to a fully extended position afterthe device is removed from the body and thereby shield a sharp end ofthe needle.
 6. The device of claim 1, wherein the two-piece telescopingplunger further comprises an inner bore, and the tubular needle residesin the inner bore when the device is in the storage position.
 7. Thedevice of claim 6, wherein the inner bore comprises a proximal closedend located inside the syringe body and a distal opening at a distal endof the syringe body.
 8. The device of claim 7, wherein the plungerextension is longitudinally slideable between the inner bore and anouter wall of the syringe body.
 9. The device of claim 6, furthercomprising medication in the syringe body.
 10. The device of claim 9,wherein a portion of the medication is located in the inner bore andsurrounding the needle.
 11. The device of claim 1, further comprising amain body, wherein the syringe body is located in the main body.
 12. Thedevice of claim 11, further including a pull plug removably engaged witha sharp end of the needle, with the pull plug also removably engagedwith the main body when the injection device is in the storage position.13. The device of claim 12, wherein the pull plug is configured uponremoval to extend the needle into a deployed position and thereby engageat least one set of needle barbs with at least one set of plug barbs.14. The device of claim 1, further comprising a pull plug removablyengaged with a sharp end of the needle, with the pull plug alsoremovably engaged with the syringe body when the injection device is inthe storage position.
 15. The device of claim 14, wherein the pull plugis configured to upon removal to pull the needle into a deployedposition and engage at least one set of needle barbs with at least oneset of plug barbs.
 16. The device of claim 1, further comprising aswitch configured to control the movement of the device from the storageposition to the deployed position.
 17. The device of claim 1, furthercomprising a spring configured to expand the plunger body relative tothe plunger extension.
 18. The device of claim 1, in which the plungerbody and the plunger extension are engaged with one another by at leastone longitudinal finger and at least one recess when the plunger is inits expanded position.
 19. An injection device, comprising: a syringebody; a two-piece telescoping plunger movably engaged within the syringebody, the telescoping plunger including a plunger body and a plungerextension; a tubular needle movably engaged with the syringe body,wherein the tubular needle is located in the telescoping plunger whenthe device is in a storage position; a medicine volume chamber withinthe syringe body; a pull plug removably engaged with a sharp end of theneedle, with the pull plug also removably engaged with the syringe bodywhen the injection device is in the storage position, wherein the pullplug is configured to upon removal to pull the needle into a deployedposition and engage at least one set of needle barbs with at least oneset of plug barbs; whereby said device is configured to expand from thestorage position to a deployment position, to expand the telescopingplunger, and to deliver a medication in the medicine volume chamberthrough the tubular needle to a body by depressing the telescopingplunger.
 20. The device of claim 19, further comprising a retractableneedle depth cover movably engaged with the syringe body and surroundingthe tubular needle when the tubular needle is in the storage position.21. The device of claim 20, in which the retractable needle depth coveris configured to retract to a pre-set depth as the tubular needle entersinto the body, thereby limiting the needle's penetrative depth into thebody.
 22. The device of claim 21, in which the pre-set depth iscontrolled by a switch.
 23. The device of claim 20, in which the depthcover is configured to return to a fully extended position after thedevice is removed from the body and thereby shield a sharp end of theneedle.
 24. The device of claim 20, wherein the two-piece telescopingplunger further comprises an inner bore, and the tubular needle residesin the inner bore when the device is in the storage position.
 25. Thedevice of claim 24, wherein the inner bore comprises a proximal closedend located inside the syringe body and a distal opening at a distal endof the syringe body.
 26. The device of claim 25, wherein the plungerextension is longitudinally slideable between the inner bore and anouter wall of the syringe body.
 27. The device of claim 24, furthercomprising medication in the syringe body.
 28. The device of claim 27,wherein a portion of the medication is located in the inner bore andsurrounding the needle.
 29. The device of claim 20, further comprising amain body, wherein the syringe body is located in the main body.
 30. Thedevice of claim 29, further including a pull plug removably engaged witha sharp end of the needle, with the pull plug also removably engagedwith the main body when the injection device is in the storage position.31. The device of claim 30, wherein the pull plug is configured uponremoval to extend the needle into a deployed position and thereby engageat least one set of needle barbs with at least one set of plug barbs.32. The device of claim 19, further comprising a switch configured tocontrol the movement of the device from the storage position to thedeployed position.
 33. The device of claim 19, further comprising aspring configured to expand the plunger body relative to the plungerextension.
 34. The device of claim 19, in which the plunger body and theplunger extension are engaged with one another by at least onelongitudinal finger and at least one recess when the plunger is in itsexpanded position.
 35. The device of claim 19, in which a portion of thetubular needle is positioned within the medicine volume chamber when theinjection device is in the storage position.
 36. An injection device,comprising: a syringe body; a two-piece telescoping plunger movablyengaged within the syringe body, the telescoping plunger including aplunger body and a plunger extension; a tubular needle movably engagedwith the syringe body, wherein the tubular needle is located in thetelescoping plunger when the device is in a storage position; a medicinevolume chamber within the syringe body; a retractable needle depth covermovably engaged with the syringe body and surrounding the tubular needlewhen the tubular needle is in the storage position; whereby said deviceis configured to expand from the storage position to a deploymentposition, to expand the telescoping plunger, and to deliver a medicationin the medicine volume chamber through the tubular needle to a body bydepressing the telescoping plunger; wherein the two-piece telescopingplunger further comprises an inner bore, and the tubular needle residesin the inner bore when the device is in the storage position, andwherein the inner bore comprises a proximal closed end located insidethe syringe body and a distal opening at a distal end of the syringebody.
 37. The device of claim 36, in which the retractable needle depthcover is configured to retract to a pre-set depth as the tubular needleenters into the body, thereby limiting the needle's penetrative depthinto the body.
 38. The device of claim 37, in which the pre-set depth iscontrolled by a switch.
 39. The device of claim 36, further comprising apull plug removably engaged with a sharp end of the needle, with thepull plug also removably engaged with the syringe body when theinjection device is in the storage position.
 40. The device of claim 39,wherein the pull plug is configured to upon removal to pull the needleinto a deployed position and engage at least one set of needle barbswith at least one set of plug barbs.
 41. The device of claim 36, furthercomprising a switch configured to control the movement of the devicefrom the storage position to the deployed position.
 42. The device ofclaim 36, further comprising a spring configured to expand the plungerbody relative to the plunger extension.
 43. The device of claim 36, inwhich the plunger body and the plunger extension are engaged with oneanother by at least one longitudinal finger and at least one recess whenthe plunger is in its expanded position.
 44. The device of claim 36, inwhich a portion of the tubular needle is positioned within the medicinevolume chamber when the injection device is in the storage position. 45.The device of claim 36, in which the depth cover is configured to returnto a fully extended position after the device is removed from the bodyand thereby shield a sharp end of the needle.
 46. The device of claim36, wherein the plunger extension is longitudinally slideable betweenthe inner bore and an outer wall of the syringe body.
 47. The device ofclaim 36, further comprising medication in the syringe body.
 48. Thedevice of claim 47, wherein a portion of the medication is located inthe inner bore and surrounding the needle.
 49. The device of claim 36,further comprising a main body, wherein the syringe body is located inthe main body.
 50. The device of claim 49, further including a pull plugremovably engaged with a sharp end of the needle, with the pull plugalso removably engaged with the main body when the injection device isin the storage position.
 51. The device of claim 50, wherein the pullplug is configured upon removal to extend the needle into a deployedposition and thereby engage at least one set of needle barbs with atleast one set of plug barbs.
 52. An injection device, comprising: asyringe body; a main body, wherein the syringe body is located in themain body; a two-piece telescoping plunger movably engaged within thesyringe body, the telescoping plunger including a plunger body and aplunger extension; a tubular needle movably engaged with the syringebody, wherein the tubular needle is located in the telescoping plungerwhen the device is in a storage position; a medicine volume chamberwithin the syringe body; a retractable needle depth cover movablyengaged with the syringe body and surrounding the tubular needle whenthe tubular needle is in the storage position; a pull plug removablyengaged with a sharp end of the needle, with the pull plug alsoremovably engaged with the main body when the injection device is in thestorage position, wherein the pull plug is configured upon removal toextend the needle into a deployed position and thereby engage at leastone set of needle barbs with at least one set of plug barbs; wherebysaid device is configured to expand from the storage position to adeployment position, to expand the telescoping plunger, and to deliver amedication in the medicine volume chamber through the tubular needle toa body by depressing the telescoping plunger.
 53. The device of claim52, in which the retractable needle depth cover is configured to retractto a pre-set depth as the tubular needle enters into the body, therebylimiting the needle's penetrative depth into the body.
 54. The device ofclaim 53, in which the pre-set depth is controlled by a switch.
 55. Thedevice of claim 52, further comprising a pull plug removably engagedwith a sharp end of the needle, with the pull plug also removablyengaged with the syringe body when the injection device is in thestorage position.
 56. The device of claim 55, wherein the pull plug isconfigured to upon removal to pull the needle into a deployed positionand engage at least one set of needle barbs with at least one set ofplug barbs.
 57. The device of claim 52, further comprising a switchconfigured to control the movement of the device from the storageposition to the deployed position.
 58. The device of claim 52, furthercomprising a spring configured to expand the plunger body relative tothe plunger extension.
 59. The device of claim 52, in which the plungerbody and the plunger extension are engaged with one another by at leastone longitudinal finger and at least one recess when the plunger is inits expanded position.
 60. The device of claim 52, in which a portion ofthe tubular needle is positioned within the medicine volume chamber whenthe injection device is in the storage position.
 61. The device of claim52, in which the depth cover is configured to return to a fully extendedposition after the device is removed from the body and thereby shield asharp end of the needle.
 62. The device of claim 52, wherein thetwo-piece telescoping plunger further comprises an inner bore, and thetubular needle resides in the inner bore when the device is in thestorage position.
 63. The device of claim 62, wherein the inner borecomprises a proximal closed end located inside the syringe body and adistal opening at a distal end of the syringe body.
 64. The device ofclaim 63, wherein the plunger extension is longitudinally slideablebetween the inner bore and an outer wall of the syringe body.
 65. Thedevice of claim 62, further comprising medication in the syringe body.66. The device of claim 65, wherein a portion of the medication islocated in the inner bore and surrounding the needle.